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Roofing/Asphalt applied base sheet

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Expert: Brian Atkins - 10/23/2009


Question
    I have a roof with either a 2 1/2 in 12 or a 3 in 12 pitched roof which was specified to have a 3-ply hot asphalt membrane (due to the low slope) with 2 piece clay tile over the membrane. The roofer "sprinkle mopped" the base sheet to the 5/8" OSB substrate. Everyone tells me that in the old days, some roofers used this application of the base sheet in lieu of mechanical fasteners, but that it is wrong. All the literature I research basically says it is wrong, but does not state why. Do You agree it is wrong, but more specifically; why is it wrong.

Answer
Hi Danny,

The only reason that it is wrong is because code states that the base sheet be fastened every 12" inches in every direction.  Anything other than code is what they would call below minimum standards and could be also called wrong.

In his defense a lot of thing they did in the old days were fine.  If your roofer knew what he he doing when he installed your roof your going to be fine.  I wouldn't be to concerned.  

And, I have never seen a roof fail because someone "sprinkle mopped" the base sheet.  

Something thing the other contractors didn't mention to you about this process is many of the 2 1/2 - 3 1/2 pitched roofs only have plywood on the eaves.  If that is the case and you try to nail it off to code all of those nails will be blowing through your eave.  

So, it's possible he did you a favor by doing that.

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Brian Atkins

Expertise

I can answer any question related to all type of roof repairs (especially tile roof repair and flat roof repair work). I can also answer most new roof or roofing related questions with the exception of questions in regards to single ply roofing (PVC) and standing seam or metal panel roofing. I have little or no experience with those applications.

Experience

I was first introduced to roofing by my father who was started his own roofing career in Orange County CA. By the time I was 10 years old I knew what most general roofing materials were and had some idea of their purpose. At the age of thirteen I started working during the summer for my Fathers roofing company Atkins Certified Custom Home Roofing. After graduating from La Quinta High School in 1988 I immediately began working full time as a journeyman roofer doing roof repair work and complete new roofs. My area of specialty and interests has always been on the roof repair side of the business. My Dad did an excellent job at teaching me the basics of roof repair. He showed me some of the techniques that were taught to him from old time roofers that took him under their belt when he was an apprentice. In 1992 my Dad signed for my first license and formed a partnership with me and I started my first roofing company in Irvine CA. This is where started to make my own niche in roofing by specializing in roof repair, dry rot repair, termite damage repair, and full roof restorations. In 1997 I took the CSLB testing and qualified for a license on my own and moved my roofing business location to Lake Forest, CA 92630. Currently I operate South County Roofing company serving the following areas of Orange County Anaheim, Anaheim Hills, Aliso Viejo, Buena Park, Brea, Cypress, Capistrano Beach, Costa Mesa, Corona Del Mar, Dana Point, El Toro, Fountain Valley, Fullerton, Foothill Ranch, Garden Grove, Huntington Beach, Irvine, Laguna Niguel, Laguna Hills, Ladera Ranch, Laguna Beach, Lake Forest, Lemon Heights, Mission Viejo, Orange, Newport Beach, Newport Coast, Rancho Santa Margarita, San Clemente, Seal Beach, Silverado Canyon, San Juan Capistrano, Santa Ana, Tustin, Trabuco Canyon, Villa Park, Westminster, Yorba Linda

Education/Credentials
La Quinta High School 1988 Westminster, Ca 92683-7098

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